fastjson学习

今天药忘吃喽~ 2021-11-27 05:24 242阅读 0赞

fastjson使用场景学习

public static void main(String[] args) {
    		/** --------- 序列化 开始--------- */
    		Student s = new Student("student", "北京市");
    		String jsonString = JSON.toJSONString(s);// 序列化 转换为 JSON
    		System.out.println(jsonString);// {"sAddress":"北京市","sName":"student"}
    		/** --------- 序列化 结束 --------- */
    
    		/** --------- 反序列化 开始--------- */
    		Student student = (Student) JSON.parseObject(jsonString, Student.class);// 反序列化
    																				// 转换为
    																				// 对象BEAN
    		System.out.println(student.toString());// Student [sName=student,
    												// sAddress=北京市]
    		/** --------- 反序列化 结束--------- */
    
    		/** --------- 反序列化为集合 开始--------- */
    		List<Student> list = new ArrayList<Student>();
    		for (int i = 0; i <= 2; i++) {
    			Student tempS = new Student("student" + (i + 1), "北京市" + (i + 1));
    			list.add(tempS);
    		}
    		String listJson = JSON.toJSONString(list);// 反序列化为集合
    		List<Student> studentList = JSON.parseObject(listJson,
    				new TypeReference<List<Student>>() {
    				});
    		System.out.println(studentList);
    		// [Student [sName=student1, sAddress=北京市1], Student [sName=student2,
    		// sAddress=北京市2], Student [sName=student3, sAddress=北京市3]]
    		/** --------- 反序列化为集合 结束--------- */
    
    		/** --------- 将对象中的空值输出 开始--------- */
    		// 1:在fastjson中,默认不输出空值的
    		Student stu = new Student("student", null);
    		String jsonStrStu = JSON.toJSONString(stu);
    		System.out.println(jsonStrStu);// {"sName":"student"}
    
    		// 2:在fastjson中,如果需要输出空值
    		String jsonStrStuNull = JSON.toJSONString(stu,
    				SerializerFeature.WriteMapNullValue,
    				SerializerFeature.WriteNullListAsEmpty);
    		System.out.println(jsonStrStuNull);// {"sAddress":null,"sName":"student"}
    		/** --------- 将对象中的空值输出 结束--------- */
    		
    		/** --------- 将对象集合 开始--------- */
    		School school = new School();
    		school.setName("清华大学");
    		for (int i = 0; i <= 2; i++) {
    			Student tempS = new Student("student" + (i + 1), "北京市" + (i + 1));
    			school.addStuList(tempS);
    		}
    		String jsonStrSchool = JSON.toJSONString(school);//序列化
    		System.out.println("jsonStrSchool : " + jsonStrSchool);
    		//jsonStrSchool : {"name":"清华大学","stuList":[{"sAddress":"北京市1","sName":"student1"},
    		//{"sAddress":"北京市2","sName":"student2"},{"sAddress":"北京市3","sName":"student3"}]}
    		
    		School schoolObject = JSON.parseObject(jsonStrSchool, School.class);//json转对象
    		System.out.println(schoolObject);//School [name=清华大学, stuList=[Student [sName=student1, sAddress=北京市1], 
    		//Student [sName=student2, sAddress=北京市2], Student [sName=student3, sAddress=北京市3]]]
    		
    		/** --------- 将对象集合 结束--------- */
    		
    		/** --------- 处理日期 开始--------- */
    		String jsonStrDateFormat = JSON.toJSONStringWithDateFormat(new Date(),
    				"yyyy-MM-dd HH:mm:ss");
    		System.out.println(jsonStrDateFormat);// "2019-07-23 14:35:59"
    		/** --------- 处理日期 结束--------- */
    	}

Student.java

class Student {
    	String sName;
    	String sAddress;
    
    	public String getsName() {
    		return sName;
    	}
    
    	public void setsName(String sName) {
    		this.sName = sName;
    	}
    
    	public String getsAddress() {
    		return sAddress;
    	}
    
    	public void setsAddress(String sAddress) {
    		this.sAddress = sAddress;
    	}
    
    	public Student() {
    	}
    
    	public Student(String sName, String sAddress) {
    		super();
    		this.sName = sName;
    		this.sAddress = sAddress;
    	}
    
    	@Override
    	public String toString() {
    		return "Student [sName=" + sName + ", sAddress=" + sAddress + "]";
    	}
    }

School.java

class School {
    	String name;
    	List<Student> stuList = new ArrayList<Student>();
    
    	public String getName() {
    		return name;
    	}
    
    	public void setName(String name) {
    		this.name = name;
    	}
    
    	public void addStuList(Student student) {
    		this.stuList.add(student);
    	}
    	
    	public void setStuList(List<Student> stuList) {
    		this.stuList = stuList;
    	}
    
    	public List<Student> getStuList(){
    		return this.stuList;
    	}
    
    	public School(String name, List<Student> stuList) {
    		this.name = name;
    		this.stuList = stuList;
    	}
    
    	public School() {
    	}
    
    	@Override
    	public String toString() {
    		return "School [name=" + name + ", stuList=" + stuList + "]";
    	}
    }